In this work, taking the most general non-Hermitian Hamiltonian without parity-time ##IMG## [http://ej.iop.org/images/0295-5075/131/3/34001/epl20234ieqn1.gif] {$(\mathcal{PT})$} symmetry and with non-Hermitian off-diagonal elements into account, we study the exceptional points of the model system. We find that there exists an exceptional ellipse in theory, compared with the exceptional ring studied in non-Hermitian ##IMG## [http://ej.iop.org/images/0295-5075/131/3/34001/epl20234ieqn2.gif] {$\mathcal{PT}$} symmetry Hamiltonian, in which the parameters in the model Hamiltonian take particular values. We also report on the dynamics of the model Hamiltonian and ##IMG## [http://ej.iop.org/images/0295-5075/131/3/34001/epl20234ieqn3.gif] {$\mathcal{PT}$} symmetry Hamiltonian. We find that they display different dynamical behaviors under different parameters. Moreover, there exists an unstable behavior of the system. Th...

中文翻译：

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没有PT对称性的非Hermitian两级系统的奇点和动力学

在这项工作中，采用没有奇偶校验时间的最一般的非厄米特哈密顿量## IMG ## [http://ej.iop.org/images/0295-5075/131/3/34001/epl20234ieqn1.gif] {$ （\ mathcal {PT}）$}对称并且考虑到非Hermitian非对角线元素，我们研究了模型系统的特殊点。我们发现，与非埃尔米特语## IMG ## [http://ej.iop.org/images/0295-5075/131/3/34001/epl20234ieqn2 .gif] {$ \ mathcal {PT} $}对称哈密顿量，其中模型哈密顿量中的参数采用特定值。我们还报告了模型哈密顿量和## IMG ## [http://ej.iop.org/images/0295-5075/131/3/34001/epl20234ieqn3.gif] {$ \ mathcal {PT} $}对称哈密顿量。我们发现它们在不同参数下显示出不同的动力学行为。而且，存在系统的不稳定行为。那个...